1. Field of the Invention
Example embodiments of the present invention relate to a method of processing a substrate, a spin unit for supplying processing materials to the substrate, and an apparatus for processing a substrate having the same. More particularly, example embodiments of the present invention relate to a method of simultaneously processing bottom and top surfaces of a substrate, a spin unit for supplying processing materials to the bottom surface of the substrate, and an apparatus for processing a substrate having the spin unit.
2. Description of the Related Art
In general, integrated circuit devices such as semiconductor memory devices are manufactured through various repeated unit processes on a semiconductor substrate such as a silicon wafer. For example, the integrated circuits are manufactured through an etching process for etching the substrate, a cleaning process for cleaning various contaminants and a drying process for drying processing materials in the etching process and the cleaning process.
An injection member has been widely used in the above unit processes such as the etching process, the cleaning process and the drying process so as to inject the processing materials, e.g., etching solutions, cleaning solutions and drying gases onto the substrate. In a conventional structure of an apparatus for the unit process, the injection member is positioned over the substrate and the processing materials are injected onto a top surface of the substrate through the injection member. Then, the processing materials on the top surface of the substrate generally spread out on the entire top surface of the substrate uniformly due to centrifugal force, because the substrate is rapidly rotated at a high angular velocity. That is, the processing materials on the substrate generally flow out towards a peripheral portion of the substrate and some of the processing materials flow off of the substrate. As a result, some of the processing materials flow onto a bottom surface of the substrate along a side surface thereof. The processing materials on the bottom surface of the substrate may cause various particles and defects.
For that reason, a cleaning member and a drying gas are positioned under a bottom surface of the substrate, and thus the residual processing materials are removed from the bottom surface of the substrate by the cleaning member and the drying gas. For example, deionized water and nitrogen (N2) gases have been widely used as a cleaning solution for the cleaning process and a drying gas for the drying process, respectively. However, the cleaning member and the drying gas merely performs the cleaning process and the drying process to the bottom surface of the substrate, and thus other process such as an additional etching process is difficult to be performed to the bottom surface of the substrate without any variation of the substrate.
So as to perform a process on the bottom surface of the substrate, the substrate is turned over and the etching solutions are injected onto the bottom substrate through the injection member over the substrate. Therefore, an addition member for turning over the substrate is required for processing the substrate, and the additional member necessarily requires an additional space to thereby decrease space efficiency of an apparatus for processing the substrate.